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arXiv · 1906.00602

Dynamics and field-induced order in the layered spin $S=1/2$ dimer system (C$_5$H$_6$N$_2$F)$_2$CuCl$_4$

Dominic Blosser·Mladen Horvatić·Robert Bewley·Severian Gvasaliya·Andrey Zheludev
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Abstract

The quasi-two-dimensional Heisenberg spin $S=1/2$ dimer system bis(2-amino-5-fluoro-pyridinium) tetrachlorocuprate(II) is studied by means of inelastic neutron scattering, calorimetry and nuclear magnetic resonance (NMR) experiments. In the absence of an applied magnetic field we find dispersive triplet excitations with a spin gap of $\Delta=1.112(15)$ meV and a bandwidth of $0.715(15)$ meV within the layers and $0.116(15)$ meV between the layers, respectively. In an applied magnetic field of $\mu_0H_c\approx 8.5$ T the spin gap is closed and we find a field induced antiferromagnetically ordered phase.

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Dominic Blosser, Mladen Horvatić, Robert Bewley, Severian Gvasaliya, Andrey Zheludev. 2019-06-03. Dynamics and field-induced order in the layered spin $S=1/2$ dimer system (C$_5$H$_6$N$_2$F)$_2$CuCl$_4$. https://doi.org/10.1103/physrevmaterials.3.074410

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